The present invention relates to a bearing assembly, in particular, a bearing assembly comprising a damper.
In gas turbine engines it is necessary to control the vibrations of the rotor in order to reduce the vibrations transmitted to the housing. This is especially important in the case of gas turbine engines for jet engines where it is necessary to reduce the vibrations transmitted to the aircraft structure.
With reference to FIG. 1, in one previously considered arrangement 100 the vibrations of the rotor shaft 108 are controlled by providing a squeeze film damper (SFD) 106 in between the bearing 102 and the bearing housing 104. The squeeze film is a small oil-filled clearance between the bearing 102 and the bearing housing. The oil film damps the radial motion of the rotating assembly and the dynamic loads transmitted to the bearing housing, thereby reducing the vibration level of the engine. Squeeze film dampers are very effective in reducing the moderate vibration that is still present after the rotor has been balanced.